package com.tutu.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.tutu.reggie.common.BaseContext;
import com.tutu.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查是否登录过滤器
 */
@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

    //路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request=(HttpServletRequest) servletRequest;
        HttpServletResponse response=(HttpServletResponse) servletResponse;

        //1.获取到本次请求的URI
        String requestURI = request.getRequestURI();

        //定义不需要处理的请求的路径
        String[] urls=new String[]{
                "/employee/login","/employee/logout",
                "/backend/**","/front/**",
                "/common/**","/user/sendMsg",
                "/user/login","/doc.html",
                "/webjars/**","/swagger-resources",
                "/v2/api-docs"};

        //2.判断本次请求是否需要处理
        boolean check=checkUrl(urls,requestURI);
        //3.如果不需要处理，则直接放行
        if(check){
            log.info("该请求无需处理:{}",requestURI);
            filterChain.doFilter(request, response);
            return;
        }
        //4.1  判断后台登录状态，若已经登录，则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("employee"));

            Long empId=(Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request, response);
            return;
        }

        //4.2  判断前台登录状态，若已经登录，则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("user"));

            Long userId=(Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }

        //5.如果未登录则返回未登录，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }


    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean checkUrl(String[] urls,String requestURI){
        for(String url:urls){
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }

        }
        return false;
    }
}
